Basement Egress window maximum sill height?

3/23/2023 at 7:09:43 PM

The National Building Code of Canada (NBCC) does not specify a maximum sill height for basement egress windows. However, it does require that the window must provide an unobstructed opening with a minimum area of 0.35 m (3.77 ft), a minimum height of 380 mm (14.96 inches), and a minimum width of 535 mm (21.06 inches). Additionally, the window well must provide a clearance of at least 550 mm (21.65 inches) in front of the window.

Please check the measures for OBC.

Regarding using furniture as a means of egress, the NBCC permits the use of as-built furniture, such as a bed, for emergency egress as long as it does not obstruct the required window opening size and does not impede access to the window itself. It is essential to ensure that the furniture does not prevent the window from opening fully, and that there is adequate clearance around the window for people to enter or exit quickly in case of an emergency.

3/24/2023 at 12:19:51 AM

There is no min. on sill heights. However the more important concern IMO?, is "how much liability for your Tenants life do you want to be responsible for??". I always make my basement secondary suite builds with windows that can be reached from the floor as you do not know what furniture a Tenant may install or where. Their physical ability to climb out a window is also a limitation. If you had a fire and the Tenant cannot escape because you made it too difficult, you could be sued or even face criminal negligence.

3/24/2023 at 11:13:11 PM

In the current (2019) Alberta Code there is no requirement for sill height for bedroom windows; perhaps it will appear in the next edition.

The Appendix of the Code contains further information on this subject; The Appendix consists of a combination of illustrations, interpretations and recommendations.

On this subject it does suggest a maximum sill height of 1.5 m and there is an illustration of a built-in desk for basement bedrooms. In this case these are simply recommendations. If you want to place a bed beneath the window a thought might be to mount a shelf above the bed which could function as a step to reach the window; just ensure it has sufficient strength to support any size of person capable of exiting through the window (i.e. up to 400 lbs?) Safe to say it the same in Ontario.